C16352_EN_005_2003-04-29

KNORR-BREMSE Systems for Commercial VehiclesPneumaticDisc BrakeSB6.../SB7...Axial and Radial Disc BrakeC16352-EN-005S e r v i c e M a n u a lIndexPage 1Overview1.1Axial Disc Brake Components (4)1.2Axial Disc Brake Identification and Service Kits (5)1.2.1Axial Disc Brake Wear Indicator Kits (5)1.3Radial Disc Brake Components (6)1.4Radial Disc Brake Identification and Service Kits (7)1.4.1Radial Disc Brake Wear Indicator Kits (7)1.5Brake Disc (8)2General Information(for Axial and Radial Disc Brakes)2.1Service Tools (9)2.2Diagnostic Equipment (9)2.3Lubrication (9)2.4Torque Requirements (9)3Description and Function3.1Axial Disc Brake Sectioned View (10)3.2Description of Operation (11)Actuation (11)3.2.1 BrakeRelease (11)3.2.2 Brake3.2.3 Brake Adjustment (automatic) (11)3.3Radial Disc Brake Sectioned View (12)3.4Description of Operation (13)Actuation (13)3.4.1 BrakeRelease (13)3.4.2 Brake3.4.3 Brake Adjustment (automatic) (13)4 Inspection Points for the Axial and Radial Disc Brake (14)4.1Safety Instructions for Service Work and Repair Work (15)(for Axial and Radial Disc Brakes)5Functional and Visual Checks(for Axial and Radial Disc Brakes)5.1Wear Check of Pads and Brake Discs (16)5.1.1 Brake Wear Check using Rubber Bush (6a, 6d) (18)5.1.2 Brake Wear Check using Rubber Bush (6b) (19)5.1.3 Brake Wear Check using Rubber Bush (6c, axially ribbed) (20)Indicators (21)5.1.4 Wear5.1.5 Diagnostic Equipment - Hand held device ZB9031-2 (21)Check (22)5.2 Adjuster5.2.1 Version without Shear Adapter (61) (22)5.2.2 Version with Shear Adapter (61) (23)Checks (25)5.3 Caliper5.3.1 Caliper Running Clearance (25)5.3.2 Caliper Movement along Guide Pins (25)5.3.3 Rubber Bush to Guide Pin Clearance (25)5.4 Check of Seals (27)5.4.1 Caliper Guide Pin Seals (27)5.4.2 Check of Tappet and Boot Assembly (13) (27)6 PadReplacement(for Axial and Radial Disc Brakes)6.1 Pad Removal (28)6.1.1 Version without Shear Adapter (61) (28)6.1.2 Version with Shear Adapter (61) (29)Fitting (30)6.2 Pad6.3 Wear Indicator Fitting (Normally Closed or Normally Open Type) (31)6.3.1 Cable Guide Type (105) (32)6.3.2 Cable Guide Type (105a) (32)6.3.3 Protection Plate (104) (32)27 Replacement of Tappet and Boot Assemblies (13) as well as Inner Seals (22)(for Axial and Radial Disc Brakes)7.1 Tappet and Boot Assemblies (13) Removal (33)7.1.1 Threaded Tubes (16) Inspection (34)7.2Inner Seals (22) Replacement (34)7.3Tappet and Boot Assemblies (13) Fitting (35)8Caliper Replacement(for Axial and Radial Disc Brakes)8.1Caliper Removal (37)8.2Caliper Fitting (38)8.2.1Fitting of Caliper (1) to Carrier (2) (38)8.2.2Fitting of Outer Boot (10) (39)8.2.3Fitting of Steel Cap (10a) (39)8.2.4Fitting of Cap (68) (40)9Replacement of Inner Boot (9) (41)(for Axial and Radial Disc Brakes)10Guide Pin Bush Replacement(for Axial and Radial Disc Brakes)10.1Brass Bush (7) Replacement (43)10.2Rubber Bush (6a or 6b) Replacement (44)10.3Rubber Bush (6c or 6d) Replacement (44)10.3.1Removal of Rubber Bush (6c or 6d) (45)10.3.2Fitting of Rubber Bush (6c or 6d) (45)11Carrier Replacement (46)(for Axial and Radial Disc Brakes)12Brake Actuator Replacement(for Axial and Radial Disc Brakes)12.1Brake Chamber Removal (47)12.2Brake Chamber Fitting (47)12.3Spring Brake Removal (48)12.4Spring Brake Fitting (48)PLEASE NOTEThis Service manual is intended for the exclusive use of trained persons within the commercial vehicle industryand workshops, and must not be passed to any third party.This service manual has been prepared to assist customers to carry out their own service work on the productand does not purport to be all-inclusive or to contain all of the information necessary for this. No responsibilityis assumed as a result of this or as a result of incorrect or inappropriate parts being fitted to the product.Knorr-Bremse SFN cannot accept any nor offer any guarantee regarding data accuracy, completeness ortimeliness. The information in this service manual does not represent any guarantees or ensuredcharacteristics in terms of the German civil code.No liability can be accepted based on the information, its use, recommendations or advice provided within thisservice manual. In no event may we be held liable for any damage or loss except in the case of wilful intent orgross negligence on our part, or if any mandatory legal provisions apply.Brand names mentioned in this service manual are not identified as such in all cases. We would emphasisehowever, that they are nevertheless subject to the provisions of trademark legislation.Text and graphics created by us are subject to our regulations on utilisation and exploitation and may only becopied or reproduced with our express permission.Any legal disputes arising from the use of this service manual or the information contained within shall besubject to German law.Failure of any individual clause of this disclaimer to comply with current legal provisions does not affect thevalidity of the remaining clauses.This disclaimer is an English translation of a German text, which should be referred to for all legal purposes.341OverviewF1.1Axial Disc Brake Components(for Wear Indicators see Section 1.2.1)4b*)Guide Pin 4c*)Guide Pin 4d*)Guide Pin 5Guide Pin 5a*)Guide Pin 6a*)Rubber Bush 6b*)Rubber Bush 6c*)Rubber Bush 6d*)Rubber Bush 7Brass Bush 9Inner Boot 10Outer Boot 10a*)Steel Cap11Pad Retainer (reinforced)12Pad (complete)12/1Pad12/2Pad Holder Spring13Tappet and Boot Assembly22Inner Seal 26Spring Clip 31Outer Boot Clip 31a*)O-Ring37Adjuster Cap 37a*)Adjuster Cap 39a*)Caliper Bolt 39b*)Caliper Bolt 39c*)Caliper Bolt 39d*)Caliper Bolt 40Caliper Bolt 40a*)Caliper Bolt44Pad Retainer Pin 45Washer 58Ring61*)Shear Adapter 68*)Cap161Tappet Bush*) VariantsSee also contents leaflet in the Service Kit51.2.1Axial Disc Brake Wear Indicator Kits Type 1Type 2Type 3Type 4Type 5Type 6ATTENTION!Use only genuine Knorr-Bremse parts!The following Service Kits are available :*)VariantsDescriptionContentsCarrier24a*), 5, 6a*), 7, 9, 10*), 31*), 39a*), 40,Guide Pins and Seal Kit58, (4b*), 4c*),4d*),5a*),6b*), 6c*), 6d*), 10a*), 31a*), 39b*), 39c*), 39d*),40a*),68*))Set for Rubber Bush4a*), 6a*), 39a*), (4b*), 6b*), 39b*))Tappet and Boot Kit (2 pieces)13, 22, 161Set for Outer Boot and Steelcap (6 pieces)10, 31, 10a*), 31a*)Adjuster Cap (10 pieces) 37, 37a*), 61*)Pad Kit (per axle)11, 12, 26, 37, 37a*), 44, 45, 61*)Wear Indicator Kit (per axle)see section 1.2.1Exchange Caliper r.h.only in assembled conditionExchange Caliper l.h.For specific Service Kit Part Numbers for each Disc Brake,see Disc Brake ProductCatalogue (Part Number Y000875) orsee Identification Plateon the Caliper1.2Axial Disc Brake Identification and Service KitsKnorr-Bremse Part No.Axle-or Vehicle Manufacturer`s No.Type of CaliperDate of ManufactureF D 00306105aAlternative to Item 105101Sensor 102Sensor104Cable Protection Plate 105Cable Guide 105a Cable Guide 112Clip115Spring Washer 116Screw117Wear Indicator Cable 119Bracket 120Bracket61.3Radial Disc Brake Components(for Wear Indicators see 1.4.1)*) VariantsSee also contents leaflet in the Sevice Kit4c*)Guide Pin 4d*)Guide Pin 5Guide Pin 5a*)Guide Pin 6a*)Rubber Bush 6b*)Rubber Bush 6c*)Rubber Bush 6d*)Rubber Bush 7Brass Bush 9Inner Boot 10Outer Boot 10a*)Steel Cap11Pad Retainer (reinforced)12Pad (complete)12/1Pad12/2Pad Holder Spring13Tappet and Boot Assembly26Spring Clip 31Outer Boot Clip 31a*)O-Ring37Adjuster Cap 37a*)Adjuster Cap 39a*)Caliper Bolt 39b*)Caliper Bolt 39c*)Caliper Bolt 39d*)Caliper Bolt 40Caliper Bolt 40a*)Caliper Bolt44Pad Retainer Pin 45Washer 58Ring61*)Shear Adapter 68*)Cap161Tappet Bush71.4.1Radial Disc Brake Wear Indicator Kits Type 1Type 2Type 3Type 4Type 5Type 6ATTENTION!Use only genuine Knorr-Bremse parts!The following Service Kits are available :*)VariantsDescriptionContentsCarrier24a*), 5, 6a*), 7, 9, 10*), 31*), 39a*), 40,Guide Pins and Seal Kit58, (4b*), 4c*),4d*),5a*),6b*), 6c*), 6d*), 10a*), 31a*), 39b*), 39c*), 39d*),40a*),68*))Set for Rubber Bush4a*), 6a*), 39a*), (4b*), 6b*), 39b*))Tappet and Boot Kit (2 pieces)13, 22, 161Set for Outer Boot and Steelcap (6 pieces)10, 31, 10a*), 31a*)Adjuster Cap (10 pieces) 37, 37a*), 61*)Pad Kit (per axle)11, 12, 26, 37, 37a*), 44, 45, 61*)Wear Indicator Kit (per axle)see section 1.2.1Exchange Caliper r.h.only in assembled conditionExchange Caliper l.h.For specific Service Kit Part Numbers for each Disc Brake,see Disc Brake ProductCatalogue (Part Number Y000875) orsee Identification Plateon the Caliper1.4Radial Disc Brake Identification and Service KitsKnorr-Bremse Part No.Axle-or Vehicle Manufacturer`s No.Type of CaliperDate of ManufactureF D 00306105aAlternative to Item 105101Sensor 102Sensor104Cable Protection Plate 105Cable Guide 105a Cable Guide 112Clip115Spring Washer 116Screw117Wear Indicator Cable 119Bracket 120Bracket1.5 Brake Disc(for Axial and Radial Disc Brakes)When replacing the Discs, please refer to the instructions of the Vehicle Manufacturer.This should also be done when fitting Knorr-Bremse Brake Discs.When replacing Discs, please adhere to the recommended bolt tightening torques.The use of non-approved Brake Discs will reduce levels of safety and invalidate warranty.Brake Discs can be ordered through the Knorr-Bremse Aftermarket Organisation.Detailed information can be found in our Disc Brake Product Catalogue (Part Number Y000875) or at .82 General Information(for Axial and Radial Disc Brakes)2.1 Service ToolsPart Number Descriptionll19252Press-in Tool for Tappet and Boot Assembly (13)ll19253Pull-in Tool for Inner Boot (9)ll19254Pull-in/Pull-out Tool for Brass Bush (7)II32202Wedged Fork for removal of Tappet and Boot Assembly (13)II36797Grooving Tool for Brass Bush (7)Z001105Press-in Tool for Steel Cap (10a)Z004198Pull-in/Pull-out Tool for Rubber Bush (6c) and (6d)Z003934Press-in Tool for Cap (68)Z004361Press-in Tool for Inner Seal (22)Service tool kit ZB9032 (Part No. II37951004EN)contains the above listed tools for items 7, 9, 10a, and 13 as well as this Service manual and a service video. The service video in English is available separately in the UK as Part No. KBP2060/1 and in otherterritories as B98283EN.The tools for items 6c, 6d, 22 and 68 are not part of the Service Tool Kit ZB9032(Part No. II37951004EN)2.2 Diagnostic EquipmentPart Number DescriptionZB9031-2 hand held device for checkingPotentiometer function (also Pad plus Discll40598F wear) when 13 pin chassis plug installed.ZB9031-2 replaces ZB90312.3 LubricationPart Number Colour Quantityll14525 white5gII32793green8gll32868 white500gZ000046green500gImportant Note:The correct grease MUST be used for each Bush !2.4 Torque RequirementsItem Number Torque Spanner Size(mm)39a; 39b;39c;Caliper Bolts (x2)180 Nm39d; 40;40a;M16x1,5 - 10.9plus 90°14Brake Chamber, Spring BrakeHexagon Nuts M16x1,5 (x2)(self-locking) EN ISO 10531180 +30 Nm249101Caliper 2Carrier4b*)Guide Pin 5*)Guide Pin 6b*)Rubber Bush 6c*)Rubber Bush 7 Brass Bush 9 Inner Boot 10*)Outer Boot 10a*)Steel Cap 11 Pad Retainer (reinforced)12 Pad (complete)13 Tappet and Boot Assembly 16 Threaded Tube 17 Bridge 18/1 Spring Brake 18/2 Brake Chamber 19 Lever20 Eccentric Bearing 22 Inner Seal 23 Adjuster Unit 24 Turning Device 26 Spring Clip 27 Spring 28 Spring 30 Chain 31 Outer Boot Clip31a*)O-Ring 32 Chain Wheel 33 Wear Sensor 37 Adjuster Cap37a*)Adjuster Cap 39b*)Caliper Bolt 40*)Caliper Bolt 43 Bolt 44 Pad Retainer Pin 45 Washer 46 Disc61*)Shear Adapter 68*)Cap161 Tappet Bush3 Description and Function3.1Axial Disc Brake Sectioned View*) Variants3.2Description of Operation(Floating Caliper principle)3.2.1Brake ActuationDuring actuation, the Push Rod of the Actuator (18/1or 18/2) moves the Lever (19). The input forces aretransferred via the Eccentric Bearing (20) to theBridge (17). The force is then distributed by theBridge (17) and the two Threaded Tubes (16) to theTappet and Boot Assemblies (13) and finally to theinboard Pad (12).After overcoming the running clearance between thePads and the Disc, the reaction forces aretransmitted to the outboard Pad (12). The clampingforces on the Pads (12) and the Disc (46) generatethe braking force for the wheel.3.2.2. Brake ReleaseAfter releasing the air pressure, the two ReturnSprings (27/28) push the Bridge (17) and Lever (19)back to the start position; this ensures a runningclearance between Pads and Disc is maintained.3.2.3Brake Adjustment (automatic)To ensure a constant running clearance betweenDisc and Pads, the brake is equipped with a lowwearing, automatic adjuster mechanism.The Adjuster (23) operates with every cycle ofactuation due to the mechanical connection withLever (19). As the Pads and Disc wear, the runningclearance increases. The Adjuster (23) and TurningDevice (24) turn the Threaded Tubes (16) by anamount necessary to compensate for this wear. Thetotal running clearance (sum of clearance both sidesof Disc) should be between 0.5 and 1.0 mm.; smallerclearances may lead to overheating problems.111230374337a*61*)3.3Radial Disc Brake Sectioned View1Caliper2Carrier 4b*)Guide Pin5*)Guide Pin 6b*)Rubber Bush 6c*)Rubber Bush 7 Brass Bush 9 Inner Boot 10*)Outer Boot 10a*)Steel Cap 11 Pad Retainer (reinforced)12 Pad (complete)13 Tappet and Boot Assembly 16 Threaded Tube 17 Bridge 18/1 Spring Brake 18/2 Brake Chamber 19 Lever20 Eccentric Bearing 22 Inner Seal 23 Adjuster Unit 24 Turning Device 26 Spring Clip 27 Spring 28 Spring 30 Chain 31 Outer Boot Clip 31a*)O-Ring 32 Chain Wheel 33 Wear Sensor 37 Adjuster Cap 37a*)Adjuster Cap 39b*)Caliper Bolt 40*)Caliper Bolt 43 Bolt 44 Pad Retainer Pin 45 Washer 46 Disc61*)Shear Adapter 68*)Cap161 Tappet Bush3.4Description of Operation(Floating Caliper principle)3.4.1.Brake ActuationDuring actuation, the Push Rod of the Actuator (18/1or 18/2) moves the Lever (19). The input forces aretransferred via the Eccentric Bearing (20) to theBridge (17). The force is then distributed by theBridge (17) and the two Threaded Tubes (16) to theTappet and Boot Assemblies (13) and finally to theinboard Pad (12).After overcoming the running clearance between thePads and Disc, the reaction forces are transmitted tothe outboard Pad (12). The clamping forces on thePads (12) and the Disc (46) generate the brakingforce for the wheel.3.4.2. Brake ReleaseAfter releasing the air pressure, the two ReturnSprings (27/28) push the Bridge (17) and Lever (19)back to the start position; this ensures a runningclearance between Pads and Disc is maintained.3.4.3Brake Adjustment (automatic)To ensure a constant running clearance betweenDisc and Pads, the brake is equipped with a lowwearing, automatic adjuster mechanism. TheAdjuster (23) operates with every cycle of actuationdue to the mechanical connection with Lever (19). Asthe Pads and Disc wear, the running clearanceincreases. The Adjuster (23) and Turning Device (24)turn the Threaded Tubes (16) by an amountnecessary to compensate for this wear. The totalrunning clearance (sum of clearance both sides ofDisc) should be between 0.5 and 1.0 mm.; smallerclearances may lead to overheating problems.134 Inspection Points for the Axial and Radial Disc BrakeDespite the use of long-life materials, it is necessary to check some of the components regularly for their general condition. The following points ensure a long-life and trouble-free operation of the disc brake. The inspection frequencies specified are minimum values. Depending on the vehicle application a more frequent check of the components may be necessary.The brake pad wear must be checked visually on a regular basis, e.g. each time the tyre pressures are checked, or at least every three months (see Sections 5.1.1, 5.1.2, 5.1.3).At least annually inspect the pad to disc running clearance and the correct fitting and condition of the Outer Boot (10) or Steel Cap (10a) and the Adjuster Cap (37 or 37a) (see Section 5.3.1).With each Pad change check for the correct functioning of the Adjuster (see Section 5.2) and the smooth operation of the caliper over its full range of movement (see Section 5.3.2). Also inspect the Tappet and Boot Assemblies (13), the Adjuster Cap (37 or 37a) and the sealing elements (6c, 9, 10, 10a, 31, 58, 68) for correct fitting and condition.The brake discs are to be checked according to the specification of the axle or vehicle manufacturer.In the unlikely event of a problem, all relevant components - e.g. Pads (12/1) and Pad HolderSprings (12/2) - must be returned in order that an objective investigation of the cause can be made.F144.1 Safety Instructions for Service Work andRepair Work(for Axial and Radial Disc Brakes)Please also refer to the relevant safety instructions forrepair work on commercial vehicles, especially forjacking up and securing the vehicle.Use only original Knorr-Bremse parts.ATTENTION!Before starting service work, ensure theservice brake and parking brake, as wellas the bus stop brake with buses, are notapplied and that the vehicle cannotroll away.Please follow service manual instructions and adhereto the wear limits of the Pads and the Discs - seeSection 5.1.Use only recommended tools - see Section 2.1.Tighten bolts and nuts to the recommended torquevalues - see Section 2.4.ATTENTION!Screw threads and tapped holes must beclean and dry (free of lubrication).After re-fitting a wheel according to the VehicleManufacturer’s recommendations, please ensure thatthere is sufficient clearance between the tyre inflationvalve, the caliper and the wheel rim, to avoid damageto the valve.After service work:Check the brake performance and the systembehaviour on a rolling road.1516PadsThe thickness of the Pads must be checked regularly dependent on the usage of the vehicle.The Pads should be checked corresponding to any legal requirements that may apply.If a Wear Indicator has not been fitted or is notconnected, this should be at least every 3 months. If friction material is less than 2mm (see E, Sketch 3),the Pads must be replaced.Minor damage at the edges is permitted (see arrow,Sketch 1).Major damage on the surface of the Pad is not permitted (see arrow, Sketch 2).ATTENTION!For optimum safety, stay within the Disc and Pad Wear Limits.DiscsMeasure thickness at thinnest point. Avoid measuring near the edge of the disc as a burr may be present.A =Disc thicknessnew condition = 45 mmworn condition = 37 mm (must be replaced) C =Overall thickness of Pad (new condition) 30mm D =Backplate 9mmE =Minimum thickness of friction material 2mmF =Minimum allowed thickness in worn conditionfor backplate and friction material 11mm (replacement of Pads necessary).If the disc dimension A ≤39 mm, it isrecommended that the Disc should be renewed together with the Pads.ATTENTION!If these recommendations are ignored, there is a danger of brake failure.Sketch 1Sketch 25 Functional and Visual Check(for Axial and Radial Disc Brakes)5.1Wear Check of Pads and Brake Discs17ATTENTION!If these recommendations are ignored, there is a danger of brake failure. If the Padsare worn down to the backplate or if Disc wear is excessive, brake performance will be severely affected and may be lost completely.Check Disc at each change of Pads for grooves and cracks.The diagram shows possible surface conditions.A 1= Small cracks spread over the surfaceare allowedB 1= Cracks less than 1.5mm deep or wide, runningin a Radial direction are allowed C 1= Grooves (circumferencial) less than 1.5mmdeep are allowed D 1= Cracks in the vanes are not allowed and theDisc MUST BE REPLACED .a = Pad contact areaNote:In case of surface conditions A 1, B 1and C 1, the Disc can continue to be used until the minimum thickness A of 37mm is reached.Knorr-Bremse Discs are normally service-free and grinding when changing Pads is not necessary.However, grinding could be useful, e.g. to increase the load-bearing surface of the Pads after severe grooving on the entire friction surface has occurred.To meet safety requirements, the minimum thickness after regrinding must be greater than 39 mm. In addition, the recommendations of the Vehicle Manufacturer MUST be followed.18The condition of the Pads can be visually determined without removing the road wheel by viewing the position of the Guide Pin (4a or 4d) in the Caliper (1).If dimension ‘C ’ is less than 1mm, a more accurate check of the Pads and Disc must be made.If necessary change the Pads - see Section 6, or the Disc - see Vehicle Manufacturer ’s recommendations.5.1.1 Brake Wear Check using Rubber Bush (6a; 6d): For all Axial and Radial Disc Brakes exceptthose listed in Section 5.1.2 and 5.1.3. These Calipers do not have a cast rib in position B (see also Section 5.1.2)B = without rib (see also Section 5.1.2)C = pin protrusion - shown in new conditionD = 1 mm or less - Pads and Disc must be checkedwith road wheel removed5.1.2 Brake Wear Check using Rubber Bush (6b): Only for Axial Disc Brakes SB 7541,SB 7551 to SB 7629,SB 7639 and Radial Disc Brakes SB 7102, SB 7112, SB 7103, SB 7113, SB 7104, SB 7114, SB 7105, SB 7115, SB 7108, SB7118, SB 7109, SB 7119, SB 7120, SB 7130.These Calipers do have a cast rib in position B (see also Section 5.1.1)The condition of the Pads can be visually determined without removing the road wheel by viewing the position of the Guide Pin (4b) in the Caliper (1).If the head of the Guide Pin (4b) is inside the Rubber Bush (6b) by a dimension D greater than 18mm, then a more accurate check of the Pads and Disc must be made.If necessary change the Pads - see Section 6, or the Disc - see Vehicle Manufacturer’s recommendations.B = with rib (see also Section 5.1.1)C = new conditionD = 18 mm or more, Pads and Disc must bechecked with road wheel removed1920The condition of the Pads can be visuallydetermined without removing the road wheel, by viewing the position of the Wear Indicator “G ”.5.1.3 Brake Wear Check using Rubber Bush (6c, axially ribbed): For all Axial and Radial Disc Brakeswhich are equiped with a Rubber Bush that is axially ribbed (see H in sketch).New Condition (see “X”)The position of Wear Indicator “G ” on the Rubber Bush (6c) in new condition.Wear Limit (see “Z”)When the Rubber Bush (6c) is retracted to the level “G ” of the Wear Indicator as shown, the wheel must be removed so that the wear of the Pads and Disc can be checked.If necessary change the Pads - see Section 6 or the Disc - see Vehicle Manufacturer ’s recommendations.5.1.4 Wear IndicatorsDue to different Vehicle Manufacturer and vehicle types there are several types of Pad Wear Indicator used.a)In-pad Normally Closed Indicator - Circuit isbroken when Pad Wear reaches limit.b)In-pad Normally Open Indicator - Circuit ismade when Pad Wear reaches limit.c)Wear Indicator using built in Potentiometer. Thisis available either as an on/off version oras a continuous signal version which can belinked to the vehicle’s electronic monitoringsystems.An optical or acoustic device may be linked to any of the above.Note:Please also refer to specifications provided by the Vehicle Manufacturer.5.1.5 Diagnostic EquipmentThe Knorr-Bremse Diagnostic Unit ZB9031-2is a hand held device suitable for vehicles that are fitted with Knorr-Bremse Disc Brakes using a continuous signal type of Wear Indicator Potentiometer.The wear condition of each brake can be measuredby connecting the device to a suitable 13 pin socket(DIN 72570) where fitted. This socket will havebeen connected to each sensor by the vehiclemanufacturer.The Diagnostic unit allows:-Quick and simple wear check.- A check of the potentiometer function.- A simultaneous check of up to six brakes,without removing the wheels.Plug to Potentiometer(Disc Brake)13-Pin Plug (DIN 72570) to VehicleA detailed instruction manual is included witheach unit.21225.2 Adjuster Check5.2.1 Version without Shear Adapter (61)The caliper assembly should be pushed inboard on its Guide Pins. Using a suitable tool, press theinboard pad (12) away from the Tappets and check the gap between Tappet and inboard pad backplate - it should be between 0.5mm & 1.0mm. If the running clearance is too small or large, the adjuster may not be functioning correctly and should be checked as follows.Remove Adjuster Cap (37).The Adjuster should be turned anti-clockwise for 2 or 3 clicks (increasing running clearance).ATTENTION!Make sure that the Ring Spanner or Socket can turn freely clockwise during following procedure.By applying the brake (to at least 2 Bar) 5 - 10 times the Spanner or Socket should turn clockwise in small increments if the Adjuster is functioning correctly (see notes below).Remove wheel.ATTENTION!Before starting service work, ensure the service brake and parking brake, as well as the bus stop brake with buses, are notapplied and that the vehicle cannotroll away.ATTENTION!Do not overload or damage the Adjuster (23). Use only 8mm Ring Spanner or 1/4”drive Socket with a lever length no greaterthan 100mm. A maximum torque of25 Nm is admissible.DO NOT use an Open Ended Spanner since this may damage the Adjuster shaft.NOTE:As the number of applications increases, incremental movement will decrease.NOTE:If the Spanner or Socket does not turn or turns only with the first application or turns forward and backward with every application, the automaticAdjuster has failed and the Caliper must be replaced. Even if Pads are not being changed, a new Adjuster Cap (37) should be fitted having lightly greased it with white grease (available as Part No. II14525 or II32868).235.2.2 Version with Shear Adapter (61)Remove wheel.The caliper assemply should be pushed inboard on its Guide Pins. Using a suitable tool, press theinboard pad (12) away from the Tappets and check the gap between Tappet and inboard pad backplate - it should be between 0.5mm & 1.0mm. If the running clearance is too small or large, the adjuster may not be functioning correctly and should be checked as follows.Pull off the Adjuster Cap (37a) using the tag, taking care not to lose the Shear Adapter (61). The Adjuster (23) must be turned with the Shear Adapter (61) anti-clockwise for 2 or 3 clicks (increasing running clearance).ATTENTION!Never turn Adjuster (23) without Shear Adapter (61) being fitted. If the given shear torque of the Shear Adapter is exceeded, then it is destroyed. Try with a new (unused) Shear Adapter. With a second failure of the Shear Adapter the Caliper must be exchanged since internal damage is present. Do not use an open ended spanner, because it may damagethe Shear Adapter (61).By applying the brake (to at least 2 Bar) 5 - 10 times the Spanner or Socket should turn clockwise in small increments if the Adjuster is functioning correctly (see notes below).ATTENTION!Before starting service work, ensure the service brake and parking brake, as well as the bus stop brake with buses, are notapplied and that the vehicle cannotroll away. ATTENTION!Make sure that the Ring Spanner or Socket can turn freely clockwise during following procedure.NOTE:As the number of applications increases, incremental movement will decrease.NOTE:If the Spanner or Socket does not turn or turns only with the first application or turns forward and backward with every application, the automaticAdjuster has failed and the Caliper must be replaced.。